Problem 503

Ely

Hello,

I am frequently having error 503 (service unavailable). This problem started when participants tried to access the experiment through multiple worker link, at the same time. Since then, this error came back thrice. Participants used their phones and were instructed to access the experiment by using a private window in Firefox because Chrome had similar problems and the error occurred. Then, participants were instructed not to access the experiment at the same time. But then even individually, participants could not access the experiment and the error occurred a second time. So, I opt to run the experiment on my computer while having a meeting with them via zoom. After a day of participation, I was finishing the experiment with a person and the data could not be transferred to JATOS and the error 503 has occurred once more. Any idea why this error persists?

kri

Hi Ely!

HTTP error code 503 means "Service Unavailable". This can have many reasons but my first guess is that somehow your JATOS server was not working at the time. Is it possible that it was overloaded (too many requests at the same time) or that it run out of memory or disk space? If this is not the case what does JATOS log say around the time when the errors happened?

Best,

Kristian

Ely

Hi Kristian,

The message on the screen was "Service unavailable. The server is temporarily unable to service your request due to maintenance downtime or capacity problems. Please try again later." But I was surprised that I could not even log in to my Jatos account until I contacted the person in charged to restart it.

Best,

Ely

kri

Ah, so JATOS or the server where JATOS runs on crashed. Again it sounds like the server doesn't have enough resources, most likely memory. How much memory does it have?

Best,

Kristian